A lot of people are under the mistaken impression that money going to the mainstream is money denied to their preferences.
If Disney vanished from the world today, the dollars flowing to them wouldn't suddenly filter out to a bunch of niche and avant-garde media. There's some overlap, but people in that overlap are already into both things and funding them. The djent fans who also love a good radio-friendly bop are already buying djent albums on Bandcamp and listening to the radio-friendly bop on Spotify.
If Disney vanished from the world today, the dollars flowing to them wouldn't suddenly filter out to a bunch of niche and avant-garde media. There's some overlap, but people in that overlap are already into both things and funding them. The djent fans who also love a good radio-friendly bop are already buying djent albums on Bandcamp and listening to the radio-friendly bop on Spotify.